CCC '16 J2 - Magic Squares

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Points: 3
Time limit: 2.0s
Memory limit: 256M

Problem type
Canadian Computing Competition: 2016 Stage 1, Junior #2

Magic Squares are square arrays of numbers that have the interesting property that the numbers in each column, and in each row, all add up to the same total.

Given a 4 \times 4 square of numbers, determine if it is a magic square.

Input Specification

The input consists of four lines, each line having 4 space-separated integers.

Output Specification

Output either magic if the input is a magic square, or not magic if the input is not a magic square.

Sample Input 1

16 3 2 13
5 10 11 8
9 6 7 12
4 15 14 1

Output for Sample Input 1


Explanation for Output for Sample Input 1

Notice that each row adds up to 34, and each column also adds up to 34.

Sample Input 2

5 10 1 3
10 4 2 3
1 2 8 5
3 3 5 0

Output for Sample Input 2

not magic

Explanation for Output for Sample Input 2

Notice that the top row adds up to 19, but the rightmost column adds up to 11.


  • 0
    Patricc  commented on June 28, 2021, 4:31 p.m.

    Can one of the admins change the fact that you have to add '\n' after the output?

    • -4
      Lava_W01f  commented on Sept. 30, 2022, 12:38 a.m. edited

      best pfp ever

  • 6
    Winbigwok  commented on March 24, 2020, 1:40 a.m.

    test cases too weak just need to check rows

    • 0
      maxcruickshanks  commented on April 15, 2022, 6:58 p.m.

      Since the original data were weak, 2 more test cases were added to prevent this solution, and all submissions were rejudged.

  • 6
    2405873453  commented on Jan. 15, 2020, 5:03 a.m.

    Everyone, if you are using java to solve this question,and having a wa because of "presentation",remember to use System.out.println instead of just print, the grader has some little problem because it is tesing all the case together, so if your out put don't move to the nxt line, what domj grader will see is something like"magicmagicnot magicmagic"

  • 16
    Plasmatic  commented on March 4, 2019, 2:43 p.m. edit 2

    this must be the predecessor to what is probably the most controversial CCC problem of all time

  • 50
    ItzMatthew  commented on Oct. 6, 2018, 6:00 p.m.

    I was working on the code for this, and my brother said that I needed to include that diagonals need to all add up as well, so my code failed like 10 times until I finally figured out that he lied to me. To publicly shame him, his name is loltrollkill

  • 0
    Y_Yousfi  commented on May 1, 2018, 10:41 p.m.

    on the first case when i use my code it outputs "magic" i get WA. i use another code that outputs "not magic" on purpose and it still gives WA. why is that?

    • 8
      Roynaruto  commented on May 2, 2018, 4:33 p.m.

      Adding a \n after magic and not magic output causes it to work in your second most recent submission.

      • -5
        Ethan_Pronev  commented on Sept. 16, 2018, 6:09 p.m.

        This comment is hidden due to too much negative feedback. Show it anyway.

      • 0
        owenzhu2012  commented on May 31, 2018, 11:06 p.m.

        Damn that helped, why is that tho?

        • 0
          Korjwist  commented on Jan. 12, 2020, 7:52 p.m. edit 2

          Shouldn't this problem be fixed?? I spent like 30 minutes trying to figure out what my problem was until I came to the comment section...

  • 0
    Roronoa_Zoro1540  commented on Aug. 10, 2017, 4:04 p.m.

    Jesus I thought the diagonals would add up too so I outputted "not magic" for one since the diagonals didn't add up lmao